WASHINGTON: The United States on Friday stepped up threats to strip Hong Kong of special trading privileges as it led Western nations in anger over China’s brazen assault on the territory’s autonomy.

US lawmakers are pressing for tough action over Hong Kong, which has become the latest front in soaring tensions between Washington and Beijing, but even some supporters of the territory’s democracy movement ask if the “nuclear option” would be effective.

Secretary of State Mike Pompeo said that a proposed national security law, submitted Friday to China’s rubber-stamp legislature, would be a “death knell for the high degree of autonomy Beijing promised for Hong Kong.” The new law would enforce punishment for “subversion” and other perceived offenses in the city, which was swept by months of massive and occasionally violent pro-democracy protests last year.

In a show of support for demonstrators, the US Congress last year overwhelmingly approved a law that would end Hong Kong’s preferential trade access to the world’s largest economy if it is no longer certified as enjoying autonomy — which Beijing promised before regaining control of the then British colony in 1997.

Pompeo said that Beijing’s latest moves would “inevitably” influence the State Department’s decision.

“The United States strongly urges Beijing to reconsider its disastrous proposal, abide by its international obligations, and respect Hong Kong’s high degree of autonomy, democratic institutions and civil liberties, which are key to preserving its special status under US law,” Pompeo said in a statement.

Pompeo had delayed the certification decision, citing the just-started session of the National People’s Congress, and lawmakers had earlier anticipated that President Donald Trump’s administration would shy away from ending Hong Kong’s trading status.

Trump had only reluctantly signed the Hong Kong act, which was strongly opposed by Beijing, as he was negotiating a deal to end a trade war with China.

Dennis Kwok, a pro-democracy lawmaker in Hong Kong, told a US-based audience on Friday that the territory’s opposition forces appreciated US efforts and urged continued vigilance, voicing fear for police crackdowns in the coming days.

He nevertheless cautioned of the risks of the United States revoking the city’s trading status, while acknowledging that many in Hong Kong were angry and would back the move.

“This is almost like a nuclear option, which once you use it, everyone will get hurt, and it will be very hard to build Hong Kong back up again,” Kwok told the conservative Heritage Foundation by videoconference.